It is established practice in the surgical field to repair defects in tissue, for instance, an inguinal hernia, through the use of PROLENE.TM. mesh (manufactured and sold by Ethicon, Inc., Somerville, N.J.). Generally the mesh is cut to a desired size for placement over the inguinal hernia. Once the sized mesh has been placed over the defect, the mesh is attached to the surrounding inguinal tissue using several known attachment means.
Once the mesh is in place, it is important that the mesh serve as a barrier over the defect in order to restrict the lower viscera in the patient's abdomen from protruding through the defect. Accordingly, it is essential that the attachment means used to secure the mesh to the inguinal tissue have an initial strength of several pounds of force in both the tensile and shear directions. Moreover, it is important that the mesh remain in place for several days so that natural adhesions can form to ensure that the mesh is sufficiently anchored to the tissue.
One common way of attaching the mesh to tissue is through the use of suture and needle. As would be expected, the suturing technique for this procedure requires a great deal of skill and is normally conducted by very experienced surgeons, especially for minimally invasive or laparoscopic procedures. Since the learning curve for laparoscopic suturing is extremely steep, many surgeons are slow to adopt this technique.
In response to the challenges associated with suturing, other fastening techniques have evolved. Accordingly, it is now common practice to use a surgical stapler such as the ENDOSCOPIC MULTI-FIRE STAPLER.TM., (manufactured and sold by Ethicon Endo-Surgery, Inc., Cincinnati, Ohio). U.S. Pat. No. 5,470,010 (Rothfuss et al.) discloses a disposable, endoscopic stapler that is used to place a number of staples at various locations of the placed mesh in order to properly secure the mesh to the tissue. Although the endoscopic stapler is efficient and easy to use for a surgeon, there is a cost issue associated with its use for this type of procedure.
In an effort to alleviate the costs associated with a disposable, multiple fire stapler, some surgeons prefer a re-usable, "single shot" stapler such as disclosed in U.S. Pat. No. 5,246,156 (Rothfuss et al.). Although there is a cost savings to the user, the procedure time is extended when using this type of stapler over the disposable, multiple fire stapler.
In addition to using surgical staplers to secure mesh to inguinal tissue to repair a hernia, other types of fasteners have been developed. One of these fasteners is a helical fastener such as disclosed in U.S. Pat. No. 5,258,000 (Gianturco). This type of fastener is also disclosed in WO 96/03925 (Bolduc et al.). However, although these types of fasteners are also easy to use and decrease the procedure time, cost is also an issue.
It is important to note that, presently, the known devices or attachment means for repairing tissue defects are mechanical devices such as endoscopic staplers or fasteners or simple needle and suture. Presently, there are no known energy-based delivery devices or energy-based methods that are capable of performing tissue repair such as that described above.